Mailosaur .NET client library.
Mailosaur allows you to automate tests that require email. You can use it with tools like Selenium, Ranorex, Robot framework etc...
You can also use it for manual testing as it gives you unlimited test email addresses or use it as a fake/dummy SMTP service.
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FSharpx is a library for the .NET platform implementing general functional constructs on top of the F# core library. Its main target is F# but it aims to be compatible with all .NET languages wherever possible.
It currently implements:
* Several standard monads: State, Reader, Writer, Either, Cont...